They are very large files (182" x 70" for the sides), they're for vehicle wrap graphics so they have to be larger. They are saved on my hard drive, using our network would be way too slow. I've done vehicle wraps in older versions of Photoshop and never had an issue like this.

Sadly, almost no one ever recovers info from PSD files that are corrupted.

If your system is prone to corrupting files, your best bet is to occasionally save your work in different master files.

I don't know how long you have been working on your file, or whether you've done it in multiple sessions, but if you have backups check them right away, before the corrupted file overwrites any older version of the file you might have backed up.

Having understood these files aren't over a network and on your internal drive, I don't see how I could help. Like station_one clearly mentioned the filesize is the 'compressed' size and when you open it with PS, your RAM may spike not allowing you to open the file. You could try tweaking your 'Scratch Disk' setting under Preferences in PS. Not sure if that'll help though. But you aren't going to lose anything by trying it.

One more thing that I've learnt the hard way - ALWAYS BACKUP your files at least on 1 location, if not on multiple drives. Since you mentioned you're using Mac OS Lion, why not try Time Machine backups? Well, your final file may still be corrupted there - but at the very least, you'll have previous versions of the file - this will save you at least half the time - you could just re-do what you've lost instead of re-doing it from scratch.

Computers should not just be "expected" to corrupt or lose data. I know mine don't, and I wouldn't tolerate it. Backups are a GREAT idea, but you shouldn't have to rely on them. Take this as your wakeup call, and implement those backups, but don't just take this failure in stride.

The reality is that sometimes computers DO lose or corrupt files. Why? There is always a reason. Failing hardware, cheap hardware, poor cables, software problems, the list goes on. Computers can seem inscrutable, but they're just complex machines, and actually CAN work perfectly.

Did you check whatever event logs would track hardware failures on your system (I'm not a Mac expert, so I'm not sure of the details)?

Is your system completely up to date?

Do you have diagnostics you can run when it's not doing anything else?

Very frustrating Adobe. I have a client waiting for work that your software keeps losing/locking me out of for no reason. Maybe take 'professional' off the box until this is resolved and replace it with beta?

I am having the same problem. I just saved my PSD file, then immediately go to open it right after closing and it tells me "Could not complete your request because the file is not compatible with this version of Photoshop. This is happening regularly. I am not working on a server nor do I use Norton Antivirus. I regularly run ONYX to clean my system and never had this problem until this version of Photoshop.

OSX: 10.7.4

Photoshop: CS5 Extended (12.1 x64)

The only other thing I've done in recent months is install a couple trials. I'm wondering if installing trials of CS6 products screws with something that makes the system THINK you've upgraded the other ones? I never installed a CS6 trial of photoshop though. Only CS6 trials of Flash Pro, Flash Builder, and InDesign. Not sure why that would have anything to do with Photoshop but...I'm also not sure why saving a PSD doesn't later let you open or have any access to your work.

I can see the file in OSX preview, but of course that doesn't get you any access to the PSD layers and other features which is why you use Photoshop. Otherwise any other software does the trick.

I ran into this same problem this morning. I ran a Google search on the error message and came up with some clues from someone who had pasted pieces into layers that exceeded the Photoshop 30,000 pixel limit. The image pieces I had copied into layers on my new file extended past the pasteboard and weren't readily visible unless you selected with Command-T (Mac). This was causing my headache.

When I enlarged my canvas to 30,000 pixels I could see the "invisible" parts of my components were larger than the pixel limit. Cropping everything to the file's pasteboard size allowed me to save and then re-open the file -- multiple times with no troubles and no need to lose my layers.